1) what challenges do arctic areas face as a result of global warming? 2) what measures could deal with the problem? 3) what do you predict will happen to arctic ecosystems if no measures are taken to reverse the problem of global warming? explain your reasoning. 4) which measures do you think are most important to pursue? support your opinion with reasons.

1.) Arctic areas face a large number of icebergs melting and ice caps in general melting as well. It also faces a large death toll in polar bears, foxes, and seals. These are issues because if the ice caps melt as well as icebergs these animals will drown and be more open to larger predators ( orcas in the seal's case).
2.) Regulations on pollution and chemicals we put in the air to stop the greenhouse effect.
3.) I believe the Arctic ecosystems will die off. The predators and prey will be out of proportion and there will be a rise in the oceans since the ice caps are frozen fresh water that fresh water will mix with the salt and there goes our fresh water we could have used as a water source.
4.) I think we should pursue the regulations on the pollution we are putting into the air and make them stricter. My reason for this is because if we were to cut back even just the slightest the ice caps would not melt as quickly as they are and we would have more time to discuss the options we have thought of to protect our icecaps as well as the environment in general. 

The "highest" point is a single point. 
there can't be more than one "highest" point.
it's not possible for every point on a line to be the "highest" one.

Could you post a picture of the number line?